Kids today, eh? They've got no idea: no idea about the basics of life such as boiling an egg or sewing on a button. No idea about being polite to their elders. No idea about the importance of thank-you letters, and certainly no idea about why you need to hold your knife and fork correctly.

Which is why, at the independent school Brighton College, the head has decided to take action. From now on, pupils aged 13-14 will be given lessons in all the above - necessary, says head Richard Cairns, because the skills will make them more attractive to potential employers.

My four kids range in age from five to 15, and I recognise all the shortcomings Cairns lists in one or other, if not all, of my offspring. Children don't come with etiquette and social skills pre-programmed: they have to learn. So I agree with Cairns in that respect: but where I part company with him is that I don't believe school should be the primary training ground for these skills.

It's not in the classroom that kids should be finding out how to boil an egg and sew on a button, still less writing thank-you letters. Schools are increasingly taking over the parents' role, and this is one of the most blatant examples yet. Of course parents need teachers to back up the messages we are (or should be) giving our kids at home. But honestly: I send my kids to school to learn maths and English, French and history. I back up the academic knowledge imparted in the classroom, but I don't expect to have to take over providing it - and nor do I expect precious learning time to be spent imparting information I'm already getting through to my children at home.

And this is why it matters: because if the task of teaching children manners and basic social skills starts being seen as something for schools to do, parents will forget it's primarily their task. And not only should schools not be teaching this sort of stuff, the truth is they can't teach it - not effectively, anyway. We learn how to behave, primarily, from home: from the example set by our parents.

Could it be, though, that the otherwise privileged children of this independent school are missing out? Perhaps that's why their head has had to step into the parenting role. Given that Brighton College is a boarding school, that makes sense: one of the most damaging aspects of the boarding system, it seems to me, is that teenagers miss out on the day-to-day role-modelling and learning that parents would otherwise provide. I was the product of a boarding school education myself: I can sew on a button and boil an egg now, but I bet my day school friends could do it sooner.

In fact, the premature curtailment of parental influence is the main reason why I wouldn't consider a boarding school for my children. Boarding schools don't provide kids with a better education, but an (in some respects) inferior one, as this initiative shows. And beyond that no school - not state, not independent - can ever be a substitute for the skills a child has to learn being imparted by his or her parents or closest guardians.